Apparatuses for tracking a solar generator to the current position of the sun, so-called trackers, are known in the prior art, wherein one example is described in DE 202 04 679 U1. The drives of such apparatuses guide the solar generators in azimuth and/or elevation direction after the sun such that the maximally possible solar radiation impinges on the solar generator. Known plants allowing tracking in azimuth and/or elevation direction comprise, for example, at the end of a supporting pole a rotating ring for adjusting the azimuth (east-west direction) and a position rod of variable length for adjusting the elevation (inclination).
Such tracking plants or “trackers”, are effectively connected to a control or regulation, respectively, which controls the tracker or its driving elements, respectively, such that the solar generator is continuously tracked to the brightest position at the sky. Such controls are constructed as individual devices and operate self-sufficiently. One example for such a control is described in DE 100 43 525 A1, which describes an apparatus for tracking a solar plant to the current position of the sun, wherein solar cells are used as sensors.
FIG. 2A shows exemplarily a known structure of a tracked solar plant. The solar plant comprises at least one solar generator 116, which comprises a plurality of solar modules 102, which generate electrical energy, for example in the form of direct current, when light from the sun 104 impinges. The solar modules 102 are mounted on a tracker 100. Adjustment of the solar generator 116 around the axes 108 and 110 is enabled via a drive of the tracker 100 not shown in FIG. 2A, wherein the drive can, for example, be mounted on a pole 106. Tracking the solar generator 116 after the sun 104 over the course of the day is enabled by the drive.
In the conventional approach shown exemplarily in FIG. 2A, in addition to the solar generator 116, the control unit 123 for the tracker 100 is provided, which is mounted on the tracker 100 in the shown example, which also carries the solar modules 102. The control unit 123 can also be provided at another position separate from the tracker 100. The control unit 123 comprises a sensor or detector 114, which generates an intensity signal in dependence on the impinging light, which is provided to a control integrated in the control unit, which itself passes a control signal to the drive 125 of the tracker 100, for ensuring optimum alignment of the solar generator 116 to the brightest point at the sky. Apart from the drive, the tracker 100 comprises also the pole 106.
The solar plant further comprises an inverter 118 which receives the direct current generated by the solar generator 116 by a connection 120 schematically shown in FIG. 2A. The inverter 118 comprises a converter means DC/AC for converting the received direct current to an alternating current. The generated alternating current is output at a schematically shown output 122 of the inverter 118.
The arrangement shown in FIG. 2A is illustrated schematically in FIG. 2B, and, as can be seen, the sensor 114 generates a sensor signal provided to a control unit 123 via the sensor signal connection 124. The control unit 123 generates a control signal for the drive 125 (motor) of the tracker 100, which is transmitted via the control signal connection 124. Further, the solar generator 116 and the inverter 118 are shown, which are connected via the electrical line 120. The inverter 118 outputs an alternating current via the line 122.
The conventional arrangement described in FIG. 2 according to which separate elements 116 and 118 or 114, 123 and 125, respectively, are used, is advantageous in that the regulation or control 123, respectively, can operate independently of the rest of the system, and can thus be operated with different solar modules and inverters.
The disadvantage of this approach, however, is that due to the plurality of elements comparatively high costs occur, and further, due to the independent operation of the tracker regulation or control 114, respectively, and the control or regulation, respectively, of the inverter 118, there is no possibility of connecting both regulations.